The aim of this core is to provide pathology services by experienced pathologists with a unique combination of extensive background in the pathology of lymphomas and breast tumors. All four projects will benefit from the Core. Having all pathology studies conducted by a specialized entity ran by expert pathologists will ensure that the same standards will be apply across the different projects. This will be critically Important for cell studies in vitro, which will benefit from uniform experimental protocols and interpretation. Project 3 and 4 will perform tumor studies in mice that require a dedicated Core. Indeed, the pathology services and facilities currently in place at Columbia University are not certified for mouse pathology and could not handle the samples in a timely manner. The Core will be ran by two experts pathologists; Drs. Bhagat and Szabolcs, lymphoma and breast cancer experts, respectively. Both have extensive experience in murine and human pathology and have been associated with several of the project leaders for years in collaborative and productive studies. Therefore, quality control is completely in place, as all procedures have been optimized, standardized and streamlined. Thus, we anticipate the most efficient usage of this core.